Chemical Processes in the Atmosphere

大气中的化学过程

• 批准号: 183982-2012
• 负责人: McLaren, Robert
• 金额: $ 2.33万
• 依托单位: York University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=593645
• 关键词: Chemical; Processes; Atmosphere

The research we perform is in the field of atmospheric chemistry. Our objectives are to further our understanding of chemical processes that occur in the troposphere, the lower layer of the atmosphere where we live and breathe. We study chemical processes in the troposphere that allow us to better understand how things that are emitted are transformed, how quickly, how the transformation takes place, the intermediates that are produced, and where the products of those transformations end up. Our particular focus is on nitrogen species and radical reactions at night and in the early morning. Radicals are small molecules that have an odd number of electrons that are particularly reactive and well suited to initiating chemical reactions. Examples of radicals include the nitrate radical (NO3), chlorine atoms (Cl), and the hydroxyl radical (OH). In the next five years, we propose to do many things. We will study changes in the chemical composition of the atmosphere vertically from the ground up, using multiple remote sensing techniques. This is important since we expect that the chemical processes that are occurring just a short distance above our heads at night, are very different that what is occurring at ground level. Since the air eventually all mixes in the morning, it is important that we know what is occurring up there the night before. In the laboratory, we will also study the formation of organic aerosols through the reaction of chlorine atoms with organic pollutants in air. We suspect that this process may be occurring above our heads in the early morning and may contribute to winter smog episodes. And we will study the nighttime formation of another species of interest to us called nitrous acid (HONO). This particular species is formed on surfaces by a complicated mechanism, and is important as a source of radicals the next day. The students that perform this research are well trained in using sophisticated instrumental methods, advanced mathematical methods, in communication skills, and in critical thinking. They are the scientists and policy makers of tomorrow.

我们进行的研究是在大气化学领域。我们的目标是进一步了解发生在对流层的化学过程，对流层是我们生活和呼吸的低层大气。我们研究对流层中的化学过程，使我们能够更好地了解排放的物质是如何转化的，转化的速度有多快，转化是如何发生的，产生的中间产物，以及这些转化的产物最终在哪里。我们特别关注氮的种类和夜间和清晨的自由基反应。自由基是具有奇数电子的小分子，特别活泼，非常适合引发化学反应。自由基的例子包括硝酸盐自由基（NO3）、氯原子（Cl）和羟基自由基（OH）。在未来的五年里，我们打算做很多事情。我们将利用多种遥感技术，从地面垂直向上研究大气化学成分的变化。这一点很重要，因为我们认为夜间发生在我们头顶附近的化学过程与发生在地面上的化学过程是非常不同的。由于空气最终会在早上混合在一起，所以我们知道前一天晚上发生了什么是很重要的。在实验室中，我们还将研究氯原子与空气中的有机污染物反应形成有机气溶胶。我们怀疑这个过程可能发生在我们头顶的清晨，并可能导致冬季雾霾的发作。我们还将研究另一种我们感兴趣的物质——亚硝酸（HONO）的夜间形成。这种特殊的物质是通过复杂的机制在表面形成的，它是第二天自由基的重要来源。进行这项研究的学生在使用复杂的仪器方法、先进的数学方法、沟通技巧和批判性思维方面受过良好的训练。他们是未来的科学家和政策制定者。